A furnace body, manufacturing equipment and manufacturing process for high-temperature diffusion oxidation annealing

Abstract

The application discloses a furnace body for high-temperature diffusion oxidation annealing process, manufacturing equipment and a manufacturing process. The furnace body comprises a base body part. The base body part is a through-cylinder structure, and is made of silicon carbide. The furnace wall of the base body part is provided with an electric heating element. The manufacturing equipment comprises a forming die and a liquid pool. The forming die comprises a columnar die body. Both ends of the die body are provided with end plates, which are a first end plate and a second end plate. The first end plate and the second end plate are respectively provided with flange parts which protrude outward from the die body. A plurality of detachable shaft bodies are connected between the flange parts of the first end plate and the second end plate. An outward-protruding plate body is arranged on the die body. The manufacturing equipment further comprises a suction pipeline, one end of which is connected to the end plate. In the application, silicon carbide is used as the material of the furnace body, so that the furnace body has strong heat resistance, heat conductivity and long service life. The design of the manufacturing equipment and the manufacturing process are in line with the structural characteristics of the furnace body, so that the furnace body can be conveniently produced and has high production efficiency.

Description

Technical Field

[0001] This invention relates to the field of solar panel manufacturing equipment technology, and in particular to a furnace body, manufacturing equipment and manufacturing process for a high-temperature diffusion oxidation annealing process. Background Technology

[0002] In the manufacturing process of solar panels, high-temperature diffusion oxidation annealing of silicon wafers is an important process. This process needs to be carried out in a high-temperature diffusion oxidation annealing furnace. Since this process needs to operate in a high-temperature environment, the choice of furnace material is very important. In the existing technology, aluminum silicate is used as the main component of the furnace body. Aluminum silicate has excellent high-temperature resistance and thermal conductivity, but the furnace body made of it is brittle and fragile, with a short service life. Therefore, the furnace body needs to be replaced at fixed intervals, which is costly and causes production interruption, affecting the production plan. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides a furnace body, manufacturing equipment and manufacturing process for high temperature diffusion oxidation annealing process that is resistant to high temperature and has a long service life.

[0004] Technical solution: To achieve the above objectives, the furnace body for the high-temperature diffusion oxidation annealing process of the present invention includes a base portion; the base portion is a cylindrical structure with both ends connected, and is made of silicon carbide; an electric heating element is provided inside the furnace wall of the base portion.

[0005] During operation, the heating element is connected to a heat source to make the space inside the substrate a high-temperature area, so that the target workpiece can be subjected to a high-temperature diffusion oxidation annealing process.

[0006] Furthermore, the base portion has a plurality of dispersed through holes; the through holes pass through both ends of the base portion; the heating elements are arranged around the through holes; and each through hole has a strip-shaped slit connecting the two internal spaces of the base portion.

[0007] By setting through holes and strip slots, on the one hand, it facilitates manufacturing and allows the heat generated by the heating element to enter the working chamber inside the base; on the other hand, when the furnace body expands due to heat or contracts due to cooling, the through holes and strip slots act as a buffer, preventing the base itself from being damaged by the stretching and compression effects caused by thermal expansion and contraction, thus extending its service life.

[0008] Furthermore, the base portion is cylindrical, and the extension direction of the through holes is parallel to the axial direction of the base portion; all the through holes are arranged in a circumferential array relative to the central axis of the base portion. This arrangement allows heat to be generated evenly on all four walls of the base portion, resulting in a uniform temperature distribution throughout the base portion and improving the working environment.

[0009] Furthermore, multiple sets of strip-shaped slots are formed on the base portion in a linear array along its axial direction. There is a gap between adjacent sets of strip-shaped slots, so that the arrangement of the strip-shaped slots and through holes does not compromise the strength of the base portion.

[0010] Furthermore, the heating element includes a heating wire.

[0011] A manufacturing apparatus for a furnace body in a high-temperature diffusion oxidation annealing process is provided for manufacturing the aforementioned furnace body. It includes a forming mold and a liquid pool. The forming mold includes a cylindrical mold body, with end plates mounted at both ends, namely a first end plate and a second end plate, at least one of which is detachable relative to the mold body. The first end plate and the second end plate each have a flange portion protruding from the mold body, and multiple detachable shafts are connected between the flange portions. A protruding plate is mounted on the mold body. The apparatus also includes a suction pipe, one end of which is connected to the end plate, and the other end of which connects to the space between the two end plates.

[0012] Furthermore, the plate can move relative to the mold, thus facilitating the removal of the plate from the slot after sintering.

[0013] To enable movement of the plates relative to the mold body, the outer wall of the mold body has slots for the plates to extend and retract. The mold body is hollow, and an inner cylinder that can slide along its inner wall is installed inside. The plates have inclined grooves formed on them, the direction of which is inclined relative to the axial direction of the mold body. The inner cylinder has pins for each plate, and these pins are positioned within the corresponding inclined grooves. Thus, the sliding of the inner cylinder relative to the mold body allows all the plates to extend and retract relative to the mold body.

[0014] Furthermore, a lifting platform is provided inside the liquid pool.

[0015] A manufacturing process for a furnace body used in a high-temperature diffusion oxidation annealing process, which is used to manufacture the aforementioned furnace body; the manufacturing process includes the following steps:

[0016] Step 1), prepare a mixture containing water, silicon carbide and silica sol;

[0017] Step 2) Immerse the molding mold in a liquid pool containing the mixture, that is, control the lifting platform to descend so that the silicon carbide in the mixture accumulates on the molding mold to form a preform;

[0018] Step 3) Sinter the molding die along with the blank to shape the blank into a furnace body blank;

[0019] Step 4): Remove the molding mold and polish the furnace body blank to obtain the finished product.

[0020] Initially, the first end plate is fixed to the mold body, the shaft is fixed to the first end plate, and the second end plate is in a disassembled state. During the manufacturing process, the heating elements are first connected in series to each of the shafts, and then the second end plate is connected to the shafts and the mold body. After the assembled molding mold is immersed in a liquid pool containing a mixture, the liquid near the molding mold is drawn out through a suction pipe to a position away from the molding mold and discharged. The discharged liquid remains in the liquid pool. In this way, the mixture in the liquid pool can move fully and circulate around the molding mold, so that the silicon carbide in the mixture can quickly converge into the annular space between the mold body, the first end plate, and the second end plate to form a preform, which can greatly improve manufacturing efficiency.

[0021] After sintering, during the process of removing the forming mold, the second end plate is removed, and then all the plates are pulled out of the corresponding strip by sliding the inner cylinder relative to the mold body. Finally, the shaft, mold body and plates are pulled out of the furnace body.

[0022] An annular gap is formed between the inner cylinder and the mold body, and the shaft is a hollow shaft. During the disassembly of the shaft and the mold body, a cooling medium such as liquid nitrogen is first injected into the shaft and the annular gap. Since the shrinkage rate of the molding mold is much greater than that of the base body, the shaft, mold body, and plates can be fully separated from the mold body. Then, by sliding the inner cylinder relative to the mold body, all plates are pulled out of the corresponding strip gaps. Finally, the shaft, mold body, and plates are removed from the furnace body. To facilitate the injection of the cooling medium, an injection device can be provided. The injection device has an injection port, a first output port connecting the annular gap, an annular groove concentrically arranged with the first output port, and a second output port leading from the annular groove to each shaft body. The first output port is directly connected to the injection port, and there are several passages between the first output port and the annular groove.

[0023] Furthermore, in the mixture, the mass ratio of silicon carbide, silica sol, and water is a:b:c, where a ranges from 5 to 20, b ranges from 1 to 5, and c ranges from 50 to 80. Using this ratio facilitates the deposition of silicon carbide onto the surface of the molding die, and the silica sol helps the silicon carbide to accumulate on the surface of the molding die and maintain the shape after accumulation, gradually forming the furnace body preform.

[0024] Beneficial effects: The furnace body, manufacturing equipment, and manufacturing process for the high-temperature diffusion oxidation annealing process of the present invention have the following advantages:

[0025] (1) Using silicon carbide as the main component of the furnace body, silicon carbide has the characteristics of stable chemical properties, high thermal conductivity, and low coefficient of thermal expansion. Therefore, the thermal expansion and contraction effect of the base material made of silicon carbide is relatively weak, making it less prone to breakage, and it also has strong high temperature resistance, which can significantly improve the service life. Using silicon carbide to replace materials such as aluminum silicate in the manufacture of the base material can solve the problem of furnace bodies made of aluminum silicate being brittle and easily broken;

[0026] (2) The furnace body has a reasonable structure. When the furnace body expands due to heat or contracts due to cooling, the through holes and strips play a buffering role. The base part itself will not be damaged by the stretching and compression effects caused by thermal expansion and contraction, which can improve the service life.

[0027] (3) The design of the manufacturing equipment and the formulation of the manufacturing process are in line with the structural characteristics of the furnace body, which can facilitate the production of the furnace body and has high production efficiency. Attached Figure Description

[0028] Figure 1 This is a structural diagram of a furnace body used in a high-temperature diffusion oxidation annealing process.

[0029] Figure 2 This is a cross-sectional view of the furnace body used in the high-temperature diffusion oxidation annealing process;

[0030] Figure 3 for Figure 2 Enlarged structural diagram of section A;

[0031] Figure 4 This is a structural diagram of the furnace body used in the high-temperature diffusion oxidation annealing process in another embodiment;

[0032] Figure 5 Structural diagrams for manufacturing equipment;

[0033] Figure 6 This is a structural diagram of the molding die;

[0034] Figure 7 This is a cross-sectional view of the molding die;

[0035] Figure 8 This is a structural diagram of the combined structure of the injection device and the molding die.

[0036] In the diagram: 10-furnace body; 11-base; 12-heating element; a-through hole; b-slot; 20-forming mold; 21-mold body; 21a-slot; 22-first end plate; 23-second end plate; 24-shaft; 25-plate; 25a-sloping groove; 26-suction pipe; 27-inner cylinder; 27a-pin; 30-liquid pool; 40-injection device; 41-injection port; 42-first output port; 43-annular groove; 44-second output port; 45-passage; 50-lifting platform. Detailed Implementation

[0037] The invention will now be further described with reference to the accompanying drawings.

[0038] like Figure 1-2 The furnace body 10 shown in the high-temperature diffusion oxidation annealing process includes a base portion 11; the base portion 11 is a cylindrical structure with both ends extending through it, and is made of silicon carbide; as shown Figure 3 As shown, an electric heating element 12 is installed inside the furnace wall of the substrate 11. Silicon carbide material has characteristics such as stable chemical properties, high thermal conductivity, and low coefficient of thermal expansion. Therefore, the substrate 11 made of silicon carbide exhibits a relatively weak thermal expansion and contraction effect, is not easily broken, and has strong high-temperature resistance, significantly extending its service life. Using silicon carbide instead of materials such as aluminum silicate in the manufacture of the substrate 11 can solve the problem of the brittleness and fragility of furnace bodies made of aluminum silicate. The electric heating element 12 includes a heating wire.

[0039] During operation, the heating element 12 is connected to a heat source to make the space inside the base 11 a high-temperature area, so that the target workpiece can be subjected to a high-temperature diffusion oxidation annealing process.

[0040] The base portion 11 has multiple dispersed through holes a; the through holes a pass through both ends of the base portion 11; the heating element 12 is arranged around the through holes a; each through hole a has a strip slit b connecting the two internal spaces of the base portion 11. By setting the through holes a and strip slit b, on the one hand, manufacturing is facilitated and the heat generated by the heating element 12 can enter the working chamber inside the base portion 11; on the other hand, when the furnace body expands due to heat or contracts due to cooling, the through holes a and strip slit b act as a buffer, preventing the base portion 11 itself from being damaged by the stretching and compression effects caused by thermal expansion and contraction, thus improving its service life.

[0041] The base portion 11 is cylindrical, and the extension direction of the through holes a is parallel to the axial direction of the base portion 11; all the through holes a are arranged in a circumferential array relative to the central axis of the base portion 11. This arrangement allows heat to be generated evenly on all four walls of the base portion 11, resulting in a uniform temperature distribution at various locations inside the base portion 11, thereby improving the working environment.

[0042] Preferably, such as Figure 4 As shown, when the base portion 11 is relatively long, multiple sets of strip slots b are formed on the base portion 11 in a linear array along its axial direction. There is a gap between adjacent sets of strip slots b, so that the arrangement of the strip slots b and the through holes a does not compromise the strength of the base portion 11.

[0043] This invention also discloses a manufacturing equipment for a furnace body used in a high-temperature diffusion oxidation annealing process, which is used to manufacture the aforementioned furnace body 10; as shown Figure 5As shown, it includes a molding die 20 and a liquid pool 30; as Figure 6-7 As shown, the molding mold 20 includes a columnar mold body 21, with end plates installed at both ends of the mold body 21, namely a first end plate 22 and a second end plate 23, at least one of the end plates being detachable from the mold body 21; the first end plate 22 and the second end plate 23 each have a flange portion protruding outward from the mold body 21, and multiple detachable shafts 24 are connected between the flange portions of the two; a protruding plate body 25 is installed on the mold body 21; it also includes a suction pipe 26, one end of the suction pipe 26 being connected to the end plate, and the end of the suction pipe 26 being connected to the space between the two end plates.

[0044] The plate 25 is movable relative to the mold 21, thus facilitating its removal from the slot b after sintering. To enable the movement of the plate 25 relative to the mold 21, the outer wall of the mold 21 has a slot 21a for the plate 25 to extend and retract. The mold 21 has a hollow structure, and an inner cylinder 27 that can slide along its inner wall is installed inside. The plate 25 has an inclined groove 25a, the extension direction of which is inclined relative to the axial direction of the mold 21. The inner cylinder 27 has a pin 27a for each plate 25, which is positioned within the corresponding inclined groove 25a. Thus, the inner cylinder 27 slides axially relative to the mold 21, allowing all the plates 25 to extend and retract relative to the mold 21.

[0045] The liquid pool 30 is equipped with a lifting platform 50, which allows the molding mold 20 to be easily immersed in the liquid pool 30 and lifted above the liquid surface.

[0046] The present invention also provides a manufacturing process for a furnace body used in a high-temperature diffusion oxidation annealing process, which is used to manufacture the aforementioned furnace body; the manufacturing process includes the following steps:

[0047] Step 1: Prepare a mixture containing water, silicon carbide, and silica sol. Preferably, the mass ratio of silicon carbide, silica sol, and water in the mixture is a:b:c, where a ranges from 5 to 20, b ranges from 1 to 5, and c ranges from 50 to 80. This ratio facilitates the deposition of silicon carbide onto the surface of the molding mold 20. The silica sol helps the silicon carbide to accumulate on the surface of the molding mold 20 and maintains the shape after accumulation, gradually forming the furnace body preform. Preferably, the mass ratio of silicon carbide, silica sol, and water is 5:1:35.

[0048] Step 2: Immerse the molding mold 20 in the liquid pool 30 containing the mixture, that is, control the lifting platform 50 to descend, so that the silicon carbide in the mixture accumulates on the molding mold 20 to form a preform;

[0049] Step 3: Sinter the molding mold 20 along with the blank to shape the blank into a furnace body blank;

[0050] Step 4: Remove the forming mold 20 and polish the furnace body blank to obtain the finished product.

[0051] Initially, the first end plate 22 is fixed to the mold body 21, the shaft 24 is fixed to the first end plate 22, and the second end plate 23 is in a disassembled state. During the manufacturing process, the heating elements 12 are first connected in series to each of the shafts 24, and then the second end plate 23 is connected to the shafts 24 and the mold body 21. After immersing the assembled molding mold 20 in a liquid pool 30 containing the mixture, the liquid near the molding mold 20 is drawn away from the molding mold 20 through the suction pipe 26 and discharged. The discharged liquid remains in the liquid pool 30. This allows the mixture in the liquid pool to move fully and circulate around the molding mold 20, enabling the silicon carbide in the mixture to quickly converge into the annular space between the mold body 21, the first end plate 22, and the second end plate 23 to form a preform, greatly improving manufacturing efficiency.

[0052] After sintering is completed, during the process of removing the forming mold 20, the second end plate 23 is removed, and then all plates 25 are pulled out from the corresponding strip seam b by sliding the inner cylinder 27 relative to the mold body 21. Finally, the shaft 24, the mold body 21 and the plates 25 are pulled out of the furnace body 10.

[0053] An annular gap is formed between the inner cylinder 27 and the mold 21, and the shaft 24 is a hollow shaft. During the removal of the shaft 24 and the mold 21, a cooling medium such as liquid nitrogen is first injected into the shaft 24 and the annular gap. Since the shrinkage rate of the molding mold 20 is much greater than that of the base part 11, the shaft 24, the mold 21, and the plate 25 can be fully separated from the mold 21. Then, by sliding the inner cylinder 27 relative to the mold 21, all the plates 25 are pulled out from the corresponding strip b. Finally, the shaft 24, the mold 21, and the plates 25 are removed from the furnace body 10. To facilitate the injection of the cooling medium, such as... Figure 8 As shown, an injection device 40 can be provided. The injection device 40 has an injection port 41, a first output port 42 connected to the annular gap, an annular groove 43 concentrically arranged with the first output port 42, and a second output port 44 leading from the annular groove 43 to each shaft 24. The first output port 42 is directly connected to the injection port 41, and there are several passages 45 between the first output port 42 and the annular groove 43.

[0054] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A furnace body (10) for a high-temperature diffusion oxidation annealing process, characterized in that, It includes a base part (11); the base part (11) is a cylindrical structure with both ends through, and is made of silicon carbide; an electric heating element (12) is provided in the furnace wall of the base part (11); the base part (11) has a plurality of dispersed through holes (a); the through holes (a) pass through both ends of the base part (11); the electric heating element (12) is arranged around the through hole (a); each through hole (a) and the internal space of the base part (11) have a strip slit (b) connecting the two; the base part (11) is cylindrical, and the extension direction of the through hole (a) is parallel to the axial direction of the base part (11); all the through holes (a) are arranged in a circular array relative to the central axis of the base part (11); a plurality of sets of strip slits (b) are formed on the base part (11) in a linear array along its axial direction.

2. The furnace body (10) for the high-temperature diffusion oxidation annealing process according to claim 1, characterized in that, The heating element (12) includes a heating wire.

3. A manufacturing equipment for a furnace body used in a high-temperature diffusion oxidation annealing process, used to manufacture the furnace body (10) as described in claim 1; characterized in that, It includes a molding mold (20) and a liquid pool (30); the molding mold (20) includes a columnar mold body (21), and end plates are installed at both ends of the mold body (21), namely a first end plate (22) and a second end plate (23); the first end plate (22) and the second end plate (23) respectively have flange portions protruding from the mold body (21), and multiple detachable shafts (24) are connected between the flange portions of the two; a protruding plate body (25) is installed on the mold body (21); it also includes a suction pipe (26), one end of the suction pipe (26) is connected to the end plate, and the end of the suction pipe (26) is connected to the space between the two end plates.

4. The manufacturing equipment according to claim 3, characterized in that, The plate (25) is movable relative to the mold (21); the mold (21) has a hollow structure and an inner cylinder (27) that can slide along its inner wall is installed inside; a groove (25a) is formed on the plate (25); the inner cylinder (27) has a pin (27a) provided for each plate (25) and the pin (27a) is placed in the groove (25a) at the corresponding position.

5. The manufacturing equipment according to claim 3, characterized in that, A lifting platform (50) is installed inside the liquid pool (30).

6. A manufacturing process for a furnace body used in a high-temperature diffusion oxidation annealing process, wherein the process is used to manufacture the furnace body as described in claim 1; characterized in that, The manufacturing process includes the following steps: Step 1), prepare a mixture containing water, silicon carbide and silica sol; Step 2), the molding die (20) used to manufacture the furnace body (10) is immersed in a liquid pool (30) containing the mixture, so that silicon carbide in the mixture accumulates on the molding die (20) to form a blank; Step 3), the forming mold (20) and the blank are sintered together to shape the blank into a furnace body blank; Step 4), remove the forming mold (20) and polish the furnace body blank to obtain the finished product.

7. The manufacturing process according to claim 6, characterized in that, In the mixture, the mass ratio of silicon carbide, silica sol, and water is a:b:c, where a ranges from 5 to 20, b ranges from 1 to 5, and c ranges from 50 to 80.

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